90 e15o with a 351 having a cross flow problem
 

Hey everybody, new to this forum and am thankful for any advise that comes this way.

I have a problem with gas going from one tank and ending up in the other. This started about a year ago and to deal with it, I just switched tanks to control the flow and to keep the tanks from overflowing I would only fill the rear and let it fill the front, then I would just switch tanks and burn off the front while it filled the rear and so on blah blah blah.

Well now the front tank only works for 5 or so miles before acting like its running out of gas even when the gauge says 3/4 full. The front tank continues to fill from the rear tank and I cannot switch over without it dying, so I have a full front tank that ends up spilling out.

where do I start with this?

Thanks in advance.

Ron

Hi Ron,
The solution to your vehicle's problem is to replace the front fuel tank pump and sender unit. They aren't cheap, but will get you back on the road, correct the over filling problem and also the loss of use of the front tank.
If I recall correctly, the bolts holding the tank straps probably are kinda rusty and it would be a good idea to spray some rust penetrant (PB Blaster or WD 40) on them before attempting removal.
I don't know if you can purchase the unit from Ford because of the age, but if you can you will get the right unit the first time. It may cost a little more, but nobody likes doing the job twice. Don't forget to also get the "O" ring that goes between the pump unit and the fuel tank, since they swell and are practically impossible to reuse.
Let us know how you make out with it.

Hi! The solution is right. But don't do it by yourself Ron! Because sometimes, it may create other problems. So try to do by experts.

I forgot to mention the most important thing !!!!!
That tank is awkward to remove when empty, however, it is very heavy when more than a little fuel is in it. If possible, find some way to siphon or pump a lot of the fuel out. It's a real dog to handle a full tank unless you have the proper equipment and lying on your back makes it tougher.
Last but not least, don't use an electric drop light anytime when doing the job. Gasoline gets loose and can hit the hot light. Use a flashlight if you have to use any kind of light.

Thanks guys.

So I spoke with 2 different mechanics at the same shop that I go to. 1 guy said that the gas from the rear tank gets sent to the front tank and drawn from there. He's says that the pump needs to be replaced and it will cost 700.

The main mechanic there said something different. He said that the diverter valve is bad and it will need to be replaced and that costs 600. Not to mention if the pump in the front tank is bad then it'll cost another 6-700.

Any ideas on this valve?

I changed a pump on a 99 dodge ram 1500 about 10 years ago. That's the extent of my experience.

Is this a hard job to do?
Can I change this valve my self?

Any recommendations are much appreciated.

Ron

I believe the valve you are referring to is called a "Mechanical Selector Valve/Reservoir."
The mechanical selector valve is controlled from the low pressure pump in the tank. Only one set of pressure and return lines is active at a time.
Not knowing what tools and facilities you have available , difficult to answer whether you could do the job or not. If in doubt, because you are working with gasoline give it some serious thought.

Afterthought------ You know by this time the pump in the front tank is tired. Replacing the pump and sending unit will solve that problem.
If,,,,,you think you need to replace that valve you will know it after replacing the pump.

Thanks hanky. I'll be thinking on this one for a couple days and let you know what I decide to do.

Ron